Oxygen Corrosion Engineering of Nonprecious Ternary Metal Hydroxides toward Oxygen Evolution Reaction
Yang Xiao, Kamran Dastafkan, Yibing Li, Tingwen Zhao, Zhen Su, Huiqian Qi, Chuan Zhao
Abstract
Facile electrocatalyst development with minimum energy consumption is highly beneficial for practical water splitting. Scale up of lab-scale active catalysts presents challenges to this end. Here, we take advantage of the spontaneous corrosion electrochemistry to make nonprecious multi-metallic hydroxides for efficient oxygen evolution reaction in alkaline electrolytes. Ternary FeNiCr and FeCoCr hydroxides are developed by oxygen- and sulfate-mediated corrosion engineering of macroporous Fe foam substrates. Cr doping is successfully achieved for regulating and accelerating the in situ phase transformation of Ni active sites into oxyhydroxide active phase to afford high intrinsic electrocatalytic activity and surface-intermediate interactions. Low overpotentials of 323 and 329 mV are achieved for delivering a large current density of 500 mA cm–2 using FeNiCr and FeCoCr electrocatalysts, respectively. Long-term stability at large current densities, reproducible performance, and facile scale up obtained suggests a great potential of designing highly efficient multi-metal electrocatalysts for water electrolysis technologies by corrosion engineering.